What is the pain in the right abdomen?

Menstruation has a lot of reasons for abdominal pain, more common are the following aspects: first, may be because the chocolate cyst caused by the right ovarian because endometriosis grows in the ovary. Menstruation odor endometrium shedding bleeding, bleeding gathered in the ovary inside does not flow out, forming a chocolate-like cyst, cyst formation mass oppression, plus menstrual pelvic and accessory uterine congestion may cause pain in the lesion site. Second, may be ectopic pregnancy, ectopic pregnancy most common site is occurred in the fallopian tube, ectopic pregnancy early main symptoms are irregular vaginal bleeding or accompanied by abdominal pain, in fact, not menstrual cramps. Third, other reasons such as appendicitis or urinary stones and appendicitis should be excluded.